Issue 6971:
Instanceof slow-path hit a lot in uglify-es benchmark

Issue description

Looking at the profile for the uglify-es test in the web-tooling-benchmark, we see that we spend a significant amount of time in the instanceof slow-paths, especially from optimized code. See the attached picture.

In the particular case of the benchmark it seems that the context specialization doesn't kick in because the instanceof is inside a function that has many closures. Simplified example:
===========================================
const A = class A {}
const makeFoo = () => x => x instanceof A;
(makeFoo())(1);
const foo = makeFoo();
console.log(foo(1));
console.log(foo(2));
%OptimizeFunctionOnNextCall(foo);
console.log(foo(3));
===========================================
Remove the (makeFoo())(1) and the instanceof is fully inlined into foo afterwards. So to address this odd performance cliff, we need to collect feedback about the right-hand side of instanceof, an INSTANCEOF_IC, which now fairly straight-forward with only Ignition and TurboFan around.